Search results for "validation"
showing 10 items of 620 documents
Risk prediction for estrogen receptor-specific breast cancers in two large prospective cohorts
2018
Source at https://doi.org/10.1186/s13058-018-1073-0. Licensed CC BY-NC-ND 4.0. Background: Few published breast cancer (BC) risk prediction models consider the heterogeneity of predictor variables between estrogen-receptor positive (ER+) and negative (ER-) tumors. Using data from two large cohorts, we examined whether modeling this heterogeneity could improve prediction. Methods: We built two models, for ER+ (ModelER+) and ER- tumors (ModelER-) , respectively, in 281,330 women (51% postmenopausal at recruitment) from the European Prospective Investigation into Cancer and Nutrition cohort. Discrimination (C-statistic) and calibration (the agreement between predicted and observed tumor risks)…
Nonmetastatic Medulloblastoma of Early Childhood: Results From the Prospective Clinical Trial HIT-2000 and An Extended Validation Cohort
2020
PURPOSE The HIT-2000-BIS4 trial aimed to avoid highly detrimental craniospinal irradiation (CSI) in children < 4 years of age with nonmetastatic medulloblastoma by systemic chemotherapy, intraventricular methotrexate, and risk-adapted local radiotherapy. PATIENTS AND METHODS From 2001-2011, 87 patients received systemic chemotherapy and intraventricular methotrexate. Until 2006, CSI was reserved for nonresponse or progression. After 2006, local radiotherapy was introduced for nonresponders or patients with classic medulloblastoma (CMB) or large-cell/anaplastic medulloblastoma (LCA). DNA methylation profiles of infantile sonic hedgehog-activated medulloblastoma (SHH-INF) were subdivided i…
Staging systems of hepatocellular carcinoma: A review of literature
2013
Hepatocellular carcinoma (HCC) is a major health problem with a high incidence and mortality all over the world. Natural history of HCC is severe and extremely variable, and prognostic factors influencing outcomes are incompletely defined. Over time, many staging and scoring systems have been proposed for the classification and prognosis of patients with HCC. Currently, the non-ideal predictive performance of existing prognostic systems is secondary to their inherent limitations, as well as to a non-universal reproducibility and transportability of the results in different populations. New serological and histological markers are still under evaluation with promising results, but they requi…
Erratum: Validation of the 2009 TNM version in a large multi-institutional cohort of patients treated for renal cell carcinoma: Are further improveme…
2011
A new edition of the TNM was recently released that includes modifications for the staging system of kidney cancers. Specifically, T2 cancers were subclassified into T2a and T2b (10 cm), tumors with renal vein involvement or perinephric fat involvement were classified as T3a cancers, and those with adrenal involvement were classified as T4 cancers. OBJECTIVE: Our aim was to validate the recently released edition of the TNM staging system for primary tumor classification in kidney cancer. DESIGN, SETTING, AND PARTICIPANTS: Our multicenter retrospective study consisted of 5339 patients treated in 16 academic Italian centers. INTERVENTION: Patients underwent either radical or partial nephrecto…
Expression of clec9a in the oral cancer microenvironment. A preliminary immunohistochemical pilot study
2021
Background The search for treatments to improve cancer survival has led to the emergence of immunotherapy and the study of the tumour microenvironment existing in neoplasms. This preliminary study aims to understand the clinical and pathological relationship of clec9a expression in oral cancer and to explore survival models for future studies. Material and methods: Immunohistochemical study that included 26 patients with a diagnosis of oral squamous cell carcinoma (OSCC) in mobile tongue and floor of the mouth. Clinical and histopathological variables were recorded, and the biomarkers clec9a for dendritic cells and CD8 and CD4 for lymphocytes were used. Results Clec9a was expressed in 58% o…
Correlation, hierarchies, and networks in financial markets
2010
We discuss some methods to quantitatively investigate the properties of correlation matrices. Correlation matrices play an important role in portfolio optimization and in several other quantitative descriptions of asset price dynamics in financial markets. Specifically, we discuss how to define and obtain hierarchical trees, correlation based trees and networks from a correlation matrix. The hierarchical clustering and other procedures performed on the correlation matrix to detect statistically reliable aspects of the correlation matrix are seen as filtering procedures of the correlation matrix. We also discuss a method to associate a hierarchically nested factor model to a hierarchical tre…
Psychometric properties of the interaction on supervised classes scale (ISCS)
2016
Objeto: La presente investigación se centra en la construcción y validación de una escala diseñada para evaluar la calidad de la clases dirigidas: Escala de Interacción en las Clases Dirigidas (EICD). Diseño/metodología/enfoque: Se trata de un estudio descriptivo correlacional. Para la elaboración de la escala se recurrió a tres fases diferenciadas en las que diferentes expertos evaluaron la adecuación de los ítems, finalmente se estudiaron las propiedades psicométricas de la versión final en una muestra de 314 socios (69.1% mujeres) con edades entre los 18 y los 77 con una media de 39.33 años (DT=12.25). Aportaciones y resultados: La escala presenta una validez y fiabilidad adecuadas, sien…
The Work Design Questionnaire: Spanish version and validation
2015
The purpose of this study is to validate the Spanish version of the Work Design Questionnaire (WDQ; Morgeson & Humphrey, 2006). Employees from three Colombian samples completed the questionnaire (N = 831). Confirmatory factor analyses revealed a 21-factor structure ( 2 /df ratio = 2.40, SRMR = .06, RMSEA = .04, CFI = .90) with adequate levels of convergent and discriminant validity. Additional support for construct validity was found from significant differences among different occupational groups (professional and nonprofessional, health-focused, commercial, and manufacturing workers). Furthermore, knowledge, social, and work context characteristics showed incremental validity over tas…
Influence of clinical and psychological variables upon the oral health-related quality of life in patients with temporomandibular disorders
2017
Background To analyze the association between the OHIP-14 and the different subtypes making up the clinical and psychological axis obtained using the RDC/TMD. Material and Methods 407 patients treated at the TMD unit of the Andalusian Healthcare Service were administered the Spanish version of the Research Diagnostic Criteria for Temporomandibular Disorders questionnaire (RDC/TMD), together with the Oral Health Impact Profile questionnaire (OHIP-14). The degree of association between the patients’ score in the OHIP-14 and the clinical and biopsychosocial variables was analyzed through bivariate and multivariate analyses, specifically through linear regression. Results 89.4% of the treated p…
Predicting the landslides triggered by the 2009 96E/Ida tropical storms in the Ilopango caldera area (El Salvador, CA): optimizing MARS-based model b…
2019
The main topic of this research was to evaluate the effect in the performance of stochastic landslide susceptibility models, produced by differences between the triggering events of the calibration and validation datasets. In the Caldera Ilopango area (El Salvador), MARS (multivariate adaptive regression splines)-based susceptibility modeling was applied using a set of physical–environmental predictors and two remotely recognized landslide inventories: one dated at 2003 (1503 landslides), which was the result of a normal rainfall season, and one which was produced by the combined effect of the Ida hurricane and the 96E tropical depression in 2009 (2237 landslides). Both the event inventorie…